1. Field of the Invention
The invention relates to stator windings for an electric machine. More particularly, it relates to stator windings consisting of the bars or coils inserted into slots of the laminated stack, in which the insulation, due to additional wrapping, has larger cross sections in some places than the slot.
2. Description of the Prior Art
Such bars or coils are described in Austrian Pat. No. 94121. In these known bars, the slot insulation is reinforced by the addition of wrapping at places which lie immediately outside the slot on the faces of the laminated stack, so that therefore the cross section of the insulation is larger there than in the slot. This is intended to prevent corona at the points where the bar leaves the slot.
Such a reinforcement of the winding cross section at the exit of the slot, outside the laminated stack, also serves to limit displacement of the bar in its axial direction. However, because of the necessity of providing tolerances, the bar cannot be completely prevented from slipping in the slot and thus, in spite of these precautions, damage to the protective outer corona coating is possible.
It is an object of the invention to secure the bars or coils of the stator winding of an electrical machine and to prevent individual winding elements or entire windings from wandering in the laminated stack.